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Random Terpolymer of Carbon Dioxide,Butadiene and Epoxides:Synthesis,Functionalization and Degradability

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Chinese Journal of Chemistry 2024年第14期42卷 1630-1636页

作者： Zi Wang Wuyi Zheng Sicong Yue Kaihao Chen Jun Ling Xufeng ni MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang310058 China Westlake Electronics Group Co. Ltd.HangzhouZhejiang310012 China

The utilization of carbon dioxide(CO_(2))as a C1 feedstock is consistently attractive,especially in the preparation of sustainable polymeric *** this contribution,a terpolymer of CO_(2),1,3-butadiene(BD)and epoxide is synthesized by scandium triflate catalyzed cationic ring-opening copolymerization ofα-ethylidene-δ-vinyl-δ-valerolactone(EVL),an intermediate derived from CO_(2)and BD,with *** obtained terpolymer with a CO_(2)content of 22 mol%has a number-average molecular weight(M_(n))up to 7.8 kg/mol and a dispersity(Đ)of *** reactivity ratios of EVL and cyclohexene oxide(CHO)are determined as 0.01 and 1.07,respectively,suggesting random characteristic of the *** preserved C=C double bonds from BD allow for the further modification of the terpolymer by photoinitiated *** yielded networks are fluorescent and *** method offers enhanced versatility to the synthesis and additional functionalization of CO_(2)-based polymers.

关键词： Ring-opening polymerization Copolymerization Carbon dioxide Butadiene Scandium triflate Fluorescence

Exosomal microRNAs in hepatocellular carcinoma,expanding research field

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World Journal of Gastroenterology 2024年第20期30卷 2618-2620页

作者： Bo-Hao Zheng Xiao-Jian ni Hou-Bao Liu Department of Biliary Surgery Zhongshan HospitalFudan UniversityShanghai 200032China Biliary Tract Disease Center of Zhongshan Hospital Fudan UniversityShanghai 200032China Biliary Tract Disease Institute Fudan UniversityShanghai 200032China Cancer Center Zhongshan HospitalFudan UniversityShanghai 200032China Shanghai Biliary Tract Minimal Invasive Surgery and Materials Engineering Research Center Shanghai 200032China

In this editorial we comment on the review by Wang et al published in the recent issue of the World Journal of Gastroenterology in *** extracellular vesicles(exosomes)play important roles in the tumor *** this review,the authors introduce the following points:(1)The composition and function of exosomal microRNAs(miRNAs)of different cell origins in hepatocellular carcinoma(HCC);(2)the crosstalk between exosomal miRNAs from stromal cells and immune cells in the tumor microenvironment and the progression of HCC;and(3)the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of *** addition,the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of HCC was *** this review,the authors give us an overview of the exosomal RNA and summarize the function of exosomal RNA in HCC,which provides a deeper understanding of exosomal miRNAs to the readers.

关键词： Exosomes MicroRNA Hepatocellular carcinoma Liver cancer Tumor microenvironment

A Deepfake Detection Algorithm Based on Fourier Transform of Biological Signal

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Computers, Materials & Continua 2024年第6期79卷 5295-5312页

作者： Yin ni Wu Zeng Peng Xia Guang Stanley Yang Ruochen Tan School of Electrical and Electronic Engineering Wuhan Polytechnic UniversityWuhan430023China School of Mathematics and Computer Science Wuhan Polytechnic UniversityWuhan430048China Paul G.Allen School of Computer Science and Engineering University ofWashingtonSeattleWA98195USA School of Computer Science and Engineering University of CaliforniaSanDiegoCA92093USA

Deepfake-generated fake faces,commonly utilized in identity-related activities such as political propaganda,celebrity impersonations,evidence forgery,and familiar fraud,pose new societal *** current deepfake generators strive for high realism in visual effects,they do not replicate biometric signals indicative of cardiac *** this gap,many researchers have developed detection methods focusing on biometric *** methods utilize classification networks to analyze both temporal and spectral domain features of the remote photoplethysmography(rPPG)signal,resulting in high detection ***,in the spectral analysis,existing approaches often only consider the power spectral density and neglect the amplitude spectrum—both crucial for assessing cardiac *** introduce a novel method that extracts rPPG signals from multiple regions of interest through remote photoplethysmography and processes them using Fast Fourier Transform(FFT).The resultant time-frequency domain signal samples are organized into matrices to create Matrix Visualization Heatmaps(MVHM),which are then utilized to train an image classification ***,we explored various combinations of time-frequency domain representations of rPPG signals and the impact of attention *** experimental results show that our algorithm achieves a remarkable detection accuracy of 99.22%in identifying fake videos,significantly outperforming mainstream algorithms and demonstrating the effectiveness of Fourier Transform and attention mechanisms in detecting fake faces.

关键词： Deepfake detector remote photoplethysmography fast fourier transform spatial attention mechanism

Growth kinetics of titanium carbide coating by molten salt synthesis process on graphite sheet surface

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1858-1864页

作者： Xiaoyu Shi Chongxiao Guo Jiamiao ni Songsong Yao Liqiang Wang Yue Liu Tongxiang Fan State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The synthesis of carbide coatings on graphite substrates using molten salt synthesis(MSS),has garnered significant interest due to its cost-effective *** study investigates the reaction process and growth kinetics involved in MSS,shedding light on key aspects of the *** involvement of Ti powder through liquid-phase mass transfer is revealed,where the diffusion distance and quantity of Ti powder play a crucial role in determining the reaction rate by influencing the C content gradient on both sides of the ***,the growth kinetics of the carbide coating are predominantly governed by the diffusion behavior of C within the carbide layer,rather than the chemical reaction *** analyze the kinetics,the thickness of the carbide layer is measured with respect to heat treatment time and temperature,unveiling a parabolic relationship within the temperature range of 700-1300℃.The estimated activation energy for the reaction is determined to be 179283 J·mol^(-1).These findings offer valuable insights into the synthesis of carbide coatings via MSS,facilitating their optimization and enhancing our understanding of their growth mechanisms and properties for various applications.

关键词： titanium carbide graphite molten salt kinetic analysis

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Long-lived lunar volcanism sustained by precession-driven core-mantle friction

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National Science Review 2024年第2期11卷 114-123页

作者： Shuoran Yu Xiao Xiao Shengxia Gong nicola Tosi Jun Huang Doris Breuer Long Xiao Dongdong ni State Key Laboratory of Lunar and Planetary Sciences Macau University of Science and Technology Planetary Science Institute State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences CAS Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Institute of Planetary Research German Aerospace Centre(DLR)

Core-mantle friction induced by the precession of the Moon's spin axis is a strong heat source in the deep lunar mantle during the early phase of a satellite's evolution, but its influence on the long-term thermal evolution still remains poorly explored. Using a one-dimensional thermal evolution model, we show that core-mantle friction can sustain global-scale partial melting in the upper lunar mantle until ～3.1 Ga, thus accounting for the intense volcanic activity on the Moon before ～3.0 Ga. Besides, core-mantle friction tends to suppress the secular cooling of the lunar core and is unlikely to be an energy source for the long-lived lunar core dynamo. Our model also favours the transition of the Cassini state before the end of the lunar magma ocean phase(～4.2 Ga), which implies a decreasing lunar obliquity over time after the solidification of the lunar magma ocean. Such a trend of lunar obliquity evolution may allow volcanically released water to be buried in the lunar regolith of the polar regions. As a consequence, local water ice could be more abundant than previously thought when considering only its accumulation caused by solar wind and comet spreading.

关键词： Moon precession orbit volcanism

Production of Functional Materials Derived from Regenerated Silk Fibroin by Utilizing 3D Printing and Biomimetic Enzyme-induced Mineralization

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Chinese Journal of Polymer Science 2024年第3期42卷 299-310,I0005页

作者： ni Chen Fei-Yu Luo Gong-Wen Yang Jin-Rong Yao Xin Chen Zheng-Zhong Shao State Key Laboratory of Molecular Engineering of Polymers Laboratory of Advanced Materials and Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Critical-sized bone defects, commonly encountered in clinical orthopedic surgery, present a significant challenge. One of the promising solutions is to prepare synthetic bone substitute materials with precise structural control, mechanical compatibility, and enhanced osteogenic induction performance, nevertheless the successful preparation of such materials remains difficult. In this study, a two-step technique,integrating an extrusion-based printing process with biomimetic mineralization induced by alkaline phosphatase(ALP), was developed. Initially,a pre-cured hydrogel of regenerated silk fibroin(RSF) with a small quantity of hydroxypropyl cellulose(HPC) and ALP was prepared through heating the mixed aqueous solution. This pre-cured hydrogel demonstrated thixotropic property and could be directly extruded into predetermined structures through a 3D-printer. Subsequently, the 3D-printed RSF-based materials with ALP underwent biomimetic in situ mineralization in calcium glycerophosphate(Ca-GP) mineralizing solution, utilizing the polymer chains of RSF as templates and ALP as a trigger for cleaving phosphate bonds of Ca-GP. The resulting 3D-printed RSF-mineral composites including hydrogel and sponge possessed adjustable compression modulus of megapascal grade and variable hydroxyapatite content, which could be controlled by manipulating the duration of the mineralization ***, these 3D-printed RSF-mineral composites demonstrated non-cytotoxicity towards rat bone marrow mesenchymal stem cells. Therefore, they may hold great potential for applications involving the replacement of tissues characterized by osteoinductivity and intricate structures.

关键词： Silk protein Alkaline phosphatase Extrusion-based printing Biomineralization

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Durable Design of Superhydrophobic Coatings with TiO_(2)Particles and Al_(2)O_(3)Whiskers for the Enhanced Anti-icing Performance

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Journal of Bionic Engineering 2024年第3期21卷 1360-1374页

作者： Weilan Liu Kunlong Li Yizhou Shen Huanyu Zhao Yaru ni Zeyu Cai Lingfeng Zhao Zhen Wang Institute of Advanced Materials(IAM) School of Materials Science and EngineeringNanjing Tech UniversityNanjing211816China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211100China Aviation Industry Aerodynamics Research Institute of China Shenyang110000China

Superhydrophobic coatings with high non-wetting properties are widely applied in anti-icing ***,the micro-nanostructures on the surfaces of superhydrophobic coatings are fragile under external forces,resulting in reduced ***,mechanical strength and durability play a crucial role in the utilization of superhydrophobic *** this study,we employed a two-step spraying method to fabricate superhydrophobic FEVE-based coatings with exceptional mechanical durability,utilizing fluorinated TiO_(2)nanoparticles and fluorinated Al_(2)O_(3)microwhiskers as the *** composite coating exhibited commendable non-wetting properties,displaying a contact angle of 164.84°and a sliding angle of 4.3°.On this basis,the stability of coatings was significantly improved due to the interlocking effect of Al_(2)O_(3)*** 500 tape peeling cycles,500 sandpaper abrasion tests,and 50 kg falling sand impact tests,the coatings retained superhydrophobicity,exhibiting excellent durability and application ***,the ice adhesion strength on the coatings was measured at only 65.4 kPa,while the icing delay time reached 271.8 s at-15℃.In addition,throughout 500 freezing/melting cycles,statistical analysis revealed that the superhydrophobic coatings exhibited a freezing initiation temperature as low as-17.25℃.

关键词： Superhydrophobic coatings Anti-icing Mechanical durability

Sodium butyrate alleviates fructose-induced non-alcoholic fatty liver disease by remodeling gut microbiota to promoteγ-amino butyric acid production

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Food Science and Human Wellness 2024年第2期13卷 961-971页

作者： Qu Chen Lei Wu Aijia Zhang Chen Wu Liuping Cai Yingping Xiao Yingdong ni Key Laboratory of Animal Physiology and Biochemistry Ministry of Agriculture and Rural AffairsNanjing Agricultural UniversityNanjing 210095China State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Institute of Agro-product Safety and NutritionZhejiang Academy of Agricultural SciencesHangzhou 310022China

Sodium butyrate(NaB)can regulate lipid metabolism and inhibit hepatic *** study aimed to investigate whether NaB can alleviate fructose-induced hepat ic steatosis via remodeling the gut microbiota and evaluate the anti-fatty liver *** results showed that NaB and NaB-remodeled gut microbiota significantly alleviated fructose-induced hepatic steatosis and increased plasma uric acid and fructose ***,both NaB and NaB-remodeled gut microbiota increased the abundance of Lactobacillus and altered the levels of plasma amino acids(upregulating gamma-amino butyric acid(GABA)and downregulating L-glutamic acid and L-arginine)in fructose-exposed *** correlation analysis showed that GABA levels positively correlated with Lactobacillus abundance,and increased GABA levels might promote the reduction of the hepatic triglyceride *** studies confirmed that GABA significantly reduced lipid deposition in mouse hepatocytes induced via fructose pretreatment in *** findings suggested that NaB could ameliorate fructose-induced hepatic steatosis by regulating gut microbiota.

关键词： Butyrate Fructose Gut microbiota Hepatic steatosis

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Development of the electric automatic steering system for agricultural vehicles

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 209-214页

作者： Guangshun An Chong Yu Juan Du Xiang Yin Youliang ni Chengqian Jin School of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000ShandongChina Nanjing Research Institute for Agricultural Mechanization of Ministry of Agriculture and Rural Affairs Nanjing 210014China

Automatic guidance of agricultural vehicles requires automatic execution of operation commands received from the navigation controller by using electronically controlled mechanisms for wheel steering,speed changing and work *** steering contributes as a prerequisite technique in automatic and semi-automatic agricultural *** research aimed to develop an electric automatic steering system that was compact in its structure and integrated into original steering mechanism in a simply and convenient way for aftermarket modification.A brushless motor and reducer assembly was utilized to provide an adequate steering torque instead of manual maneuver.A rapid assembling approach was proposed by passing the steering shaft through the hollow output shaft.A digital proportional-integral-differential(PID)algorithm was implemented to calculate the rotation speeds and directions by comparing the desired angle and the actual angle,which was implemented in a printed circuit board with a microcontroller unit(MCU)and interface *** unmanned wheeled tractor was applied as test platform to integrate the newly developed electric automatic steering *** were conducted to evaluate its performance in terms of stability and *** autonomous navigation system guided the tractor along target paths in the field by sending steering commands to the electric automatic steering *** results show that the steering angle error was less than 0.81°when desired steering angle was less than 10°.The lateral error difference was no more than 4.76 cm when repeating following the same target path,which indicated that the electric automatic steering system responded accurately and robustly to steering commands.

关键词： automatic steering automatic navigation agricultural vehicles